Use checkboxes to select node libraries

[mmisol]

Purpose

Changes the publish package dialog to use checkboxes rather than a
context menu to select which dlls are node libraries. Also adds an
instructive text on top to further guide users.

Snapshot:

Declarations

Check these if you believe they are true

• The codebase is in a better state after this PR
• Is documented according to the standards
• The level of testing this PR includes is appropriate
• User facing strings, if any, are extracted into *.resx files
• All tests pass using the self-service CI.
• Snapshot of UI changes, if any.
• Changes to the API follow Semantic Versioning and are documented in the API Changes document.
• This PR modifies some build requirements and the readme is updated

[QilongTang]

LGTM. Curious if you had the chance to test it locally to check if the pkg.json has IsNodeLib set correctly

[mmisol]

@QilongTang I tested it but I had to do some code changes to run it outside Revit (had some errors otherwise) and also avoid the actual publishing. It should be equivalent to actual usage I think.

[QilongTang]

@QilongTang I tested it but I had to do some code changes to run it outside Revit (had some errors otherwise) and also avoid the actual publishing. It should be equivalent to actual usage I think.

Great!